1. Field of the Invention
The present invention relates to a liquid crystal panel which can be used for a large scale display at, for example, a word processor, personal computer, and the like.
2. Description of the Related Art
As a liquid crystal display device whereby a color display is possible, there is a demand for a highly multiplexed liquid crystal display device by which a black and white display can be made by a simple matrix display, wherein the matrix has a large number of multiplexed lines. A conventional liquid crystal display panel comprises a pair of transparent substrates provided with a transparent electrode and an aligning film on the inside surfaces thereof, respectively, a liquid crystal layer sealed between the transparent substrates, and two polarizers sandwiching the transparent substrates, wherein liquid crystal molecules are twisted between the transparent substrates. The liquid crystal display device is divided into the following two groups, depending on a twist angle of the liquid crystal molecules: A twisted nematic (TN) type device having a twist angle of about 90.degree. (display by rotation of light), and a super-twisted nematic (STN) type device having twist angle of more than 90.degree. (display by birefringence of light). In the above-mentioned TN-type liquid crystal display panel, however, an abrupt change of light transmittance in relation to applied voltage does not occur and strongly dependent on the viewing angle, and therefore, a high information density display having about 400 black lines on the white background cannot be obtained by a simple matrix structure, since with a high information density display, i.e., having a small duty ratio, such as 1/200, i.e., 200 multiplexed lines, close voltages are applied to selected and unselected elements respectively.
In the above-mentioned STN-type liquid crystal display panel, an abrupt change of light transmittance in relation to applied voltages can occur, and thus a high information density display can be obtained. But this STN-type uses light birefringence for the display, which has a large light dispersion at a specific wave length and thus causes coloration of the display, such as a black image on yellow-green background (yellow mode) or a blue image on a white background (blue mode). As a result, it is difficult to obtain not only a black and white display but also a color display, even when a color filter is used.
An object of the present invention is to provide a liquid crystal display panel wherein an abrupt change of light transmittance in relation to applied voltage occurs and a light dispersion of transmitted light is reduced, i.e., to provide a liquid display panel whereby a large capacity display with a large number of white lines on a black background can be obtained.